I have a question regarding the max speed of diesel engines. On a prototype diesel, is the max speed available under load? Reason for the question: I'd like to as much as possible configure my DCC loco's performance to match the prototype. For example in Wiki it says the max on an SD60 is 70mph. I can put my model on the track and use a stop watch to set the max speed in the decoder to match 70 mph, but of course once I add a string of cars the speed at max throttle is much slower than the one I set under no load conditions.
Max speed would depend on a myriad of factors! Over the past 10 days, I've watched 2 trains stall (before reaching the curve) on Horseshoe and quite a few survive owing to AC traction as they creeped at a brisk walk pace!! Then, I've watched trains haul the proverbial donkey at La Plata!
Speed isn't the issue. On our older EMD engines there is a time limit Once we hit the red (1200 amps then its 15 minutes, then 1300 amps is 12 minutes, then 1500 amps is 5 minutes). We can easily burn out a traction motor or even burn the rail from spinning wheels but not moving. The newer units don't have these short time ratings.